Label-free detection of Staphylococcus aureus captured on immutable ligand arrays

ACS Appl Mater Interfaces. 2013 Jul 10;5(13):6404-11. doi: 10.1021/am4016236. Epub 2013 Jun 28.

Abstract

The rapid capture and label-free detection of Staphylococcus aureus , an opportunistic bacterium that can infect upon contact, can be performed using periodic microarrays of ligand-protein conjugates created by noncontact (inkjet) printing, darkfield imaging conditions, and a FFT-based readout method. Ink solutes were prepared using bovine serum albumin (BSA) conjugated to a glycan with high affinity for bacterial adhesins and printed as dot-matrix arrays with periodicities of 80-120 μm using a thermal injection method. Upon exposing the glycan-BSA microarrays to live strains of S. aureus , patterns emerge that can be detected under optical darkfield conditions. These patterns can be decoded by fast Fourier transform (FFT) analysis to generate fault-tolerant readout signals that correspond to the capture of S. aureus, with a limit of detection between 10(2) and 10(3) cfu/mL. Inkjet printing provides independent control over array periodicity, enabling FFT signals to be assigned to specific frequencies in reciprocal k-space.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adhesins, Bacterial / chemistry
  • Humans
  • Ligands
  • Protein Array Analysis / instrumentation
  • Protein Array Analysis / methods*
  • Staphylococcal Infections / microbiology
  • Staphylococcus aureus / chemistry*
  • Staphylococcus aureus / isolation & purification*

Substances

  • Adhesins, Bacterial
  • Ligands